Square socket screw with side slots



Sept. 19, 1939.

F. K. BROWN 2,173,707

SQUARE SOCKET SCREW WITH SIDE SLOTS Filed Nov. 27, 1937 Patented Sept. 19, 1939 UNITED STATES somnn'socxn'r scar-2w wrrn smE SLOTS Frank K. Brown, South Dartmouth, Mass as signer to Continental .Screw Company, Bedford, Mass, a corporation of Massachusetts Application November 2'1, 1937, Serial No. 1'l6,885

1 Claim,

My present invention is an improved screw structure and is directed to an improvement in the head,-wherein both a square socket for cooperation with a socket wrench, and a plurality 5 of slots opening from said socket on the respective sides for cooperation with a common screwdriver, are provided.

My present invention is an improvement on the combined socket and slotted screw structure of my prior Patent No. 2,082,148, dated June 1, 1937, wherein I have described, illustrated, and claimeda particular form of socket and slot screw structure. In my said prior patent I have shown a form of square or rectangular'socket with a plurality of rectangular slots opening from the corners of the socket, and all being formed by a heading or swaging operation, with the periphery of the head ofthe screw unbroken, the slots terminating short of the periphery of the screw head. a

In my present improved form I utilize a square socket with substantially vertical side walls, as shown in my said prior patent, and provide the diametrically opposite pairs of rectangular. slots opening from the socket from each side wall and extending toward the periphery of the screw lsilead to constitute the screwdriver-engaging ots. In my said prior patent the construction as therein shown in preferred form illustrated rectangular slots opening from each corner of the socket. This prior construction thereby shortened the side walls when engaged by a straight socket wrench and also necessitated somewhat short slots because the distance from the cdrners of the socket to the periphery were limited.

In my present'invention wherein I form the rectangular slots directly from the center of the side wall, I am enabled to maintain the socket;

40 with the corners intact for better engagement and turning when a socket wrench is used and, furthermore, am enabled to use the rectangular slots of considerably'greater length than intheform in my said patent. Thus the available dis- 46 tance between the square side walls of thesocket and the periphery of the screw head affords the grea'ikst length possible to be found in the metal of the screw head between the socket and the periphery and, hence, by forming the common 50 screwdriver-receiving slots at this point, I produce a screw head with greater contact of metal in the slots for the common screwdriver, as well as a better socket wrench contact because of the corners being square and uncut.

It will be appreciated that the strain and wood screw, bolt, nut.

tension between a driving implement and a screw socket or slot of any kind is greatest at the extreme point of contact between the driving element and the screw, and my present construction utilizes the advantage of this principle. 6 While my present invention permits the use either of a socket wrench or a. common screwdriver, it also facilitates the use of a screwdriving implement combining both the socket wrench features and one or more pairs of wings, such it! for example as shown in my copending application Ser. No. 172,611, filed Nov. 3, 1937, wherein I have illustrated andclaimed a special screwdriver constituting a combined socket and screw-- driver, constructed and arranged either, for the 18 form shown in my said prior patent or the form of socket and slot screw head herein illustrated.

Referring to the drawing,

Fig. 1 is a plan view of a screw head embodying my present invention of a square socket re- 20 cess in the head together with a plurality of rectangular op nings extending toward the periphery from the center of each side wall;

Fig. 2 is a cross-sectional view on the line 2-2 of Fig. 1; Fig. 3 is a cross-sectional view on the line 3-3 of Fig. 1;

Fig. 4 is a perspective view;

Fig. 5 is a view illustrating my present improved screw head with a socket wrench for the so screwdriver;

Fig. 6 illustrates same with a combined socket and four-winged type of screwdriver, and

Fig. 7 illustrates my present invention with a combined'socket and two-winged type of screw- :5 driver.

Referring to the drawing, I illustrates the top of the head of the screw with the usual bevelled portion 2 between the head and the threaded shank 3, which shank may be threaded for a 0 or' any other desired threaded arrangement. Formed in the head I is a central rectangular recess 5 being here shown as square, with four side walls 6, I, 8, and 9 extending downwardly into the head of the screw 45' and with rectangular recesses or openings extending from the center of each of said side walls toward the periphery of the head. These rectangular recesses are designated as l6, I1, 18, and I! opening-respectively from the side walls so '6,1, 8,and9.-

Referring to Fig-5 illustrating my present socket and slot screw head arranged for cooperation with a socket wrench 20, having squarev or rectangular faces adapted to engage, contact 55 with, and operate the screw head, the socket wrench is inserted in the recess 5, and it will be appreciated that each corner 2| of the socket wrench 20 will engage adjacent side walls of the recess 5 within the corresponding corner recesses 22-22 in the socket 5. Thus a full leverage is obtained between the wrench 2| and the side walls and comers'of the socket 5.

Referring to the form shown in Fig. 6, I have illustrated a combined socket and wing type of wrench having the square socket portion 2 and a plurality of side wings 21 adapted to engage the rectangular recesses l6, l1, l8, and I! in any position in which they may be in alignment when the wrench is fitted into the screw head.

In Fig. '7 I have illustrated a still further modified form of wrench 3| having a square socket portion 3| and a single pmr of oppositely positioned wings 32-42 which are adapted to engage any opposite pair of the rectangular slot openings It to Is inclusive in the screw head.

It will, of course, be also appreciated that a common screwdriver may be utilized which would span the central recess 5 and engage an opposite pair of rectangular recesses and ill, or H and I! but I prefer to utilize one of the special types of screwdrivers as illustrated, combining both the socket wrench feature and the winged features, which screwdriver invention is claimed broadly in my said copending application Ser. No. 172,611 filed Nov. 3, 1937.

The winged members 21 of the type of screwdriver shown at 25 or the wings 32 designated at are preferably bevelled, substantially as shown in the drawing, so as to fit the usual bevelling of the rectangular slots and, furthermore, this construction permits a screwdriver to fit and engage screw heads of difler'ent sizes within a considerable range, the central socket recess 5 being substantially of standard size while the length of the rectangular slots [6 to I9 is somewhat proportional to the diameter of the head of the screw, as will be readily appreciated.

I claim: 7

A screw having a headformed with its periphery unbroken, containing'therein a central square socket recess formed in the head with substantially. perpendicular side walls, and extending axially of the screw a depth substantially equal to the extent of the head, four slotsopening from said socket each slot positioned centrally of each side of said squared socket, each slot being rectangular in cross-section, the end wall of each slot tapering from the bottom of the squared socket outwardly and upwardly, said slots being in pairs diametrically oppositeeach other and symmetrically arranged and all slots terminating within the periphery of the screw head.

FRANK K. BROWN. 

